Paper manufacture



Patented Nov. 1, 1932 PATENT OFFICE STATES HAROLD ROBERT B-AFTON, OF ANDOVER, MAS SAGHUSETTS, ASSIGNOR TO RAFIFOLD PROGESS CORPORATION, A CORPORATION OF MASSACHUSETTS PAPER MANUFACTURE Ho Drawing.

' the manufacture of sized paper filled with alkaline filler.

An important object is the use as sizing agent of sapnifiable material in substantially or preponderatingly unsaponified form.

A further object is the use of rosin in substantially or preponderatingly unsaponified form.

A further objectis the employment of the principle of adding materials under conditions favoring the minimizin of the time and/or intimacy of contact oi the constituents of the mix in connection with the sizing of paper filled withalkaline filler employing sizing material comprising saponifiable material in substantially or preponderatingly unsaponified form.

Other objects and advantages of this invention will become apparent during the course of the following description.

In numerous of my patents, for example No. 1,819,441, issued August 18, 1931, and NOS. 1,803,645, 1,803,648, 1,803,651, and 1,803,652, issued May 5, 1931, I have disclosed the sizing of paper filled with alkaline filler by the employment of a substantially unsaponifiable material such as paraflin in emulsified form. In other of my patents for I with an alkaline filler.

example, Nos. 1,803,643 and 1,803,647, issued May 5, 1931, l broadly cover the addition of alum or the like at the wet end of the paper machine, or in the. beater and at the wet end of the paper machine, in the practice of the sizing, with any su table size, of paper filled Particularly 1 disclose therein the use as sizes of partially or completely saponifiable materials in saponified form, and preferably the use of size such as ordinary rosin size.

Rosin inpapermaking is ordinarily employed in the form of rosin soap in which the rosin is wholly or partially saponified, in the latter case the saponified rosin holding the unsaponified rosin in emulsion form. In practice, the free rosin, i. e. the unsaponilied rosin, even in such soaps as are known as high free rosin soaps, does not run much 3 Application filed December 30, 1931 Serial No. 584,012.

above per cent. of the total rosin present, and although it is perhaps considered theoretically feasible to make a usable soap with as high as 55 per cent. free rosin, in practice per cent. may be said to be the upper l mit. It will thus be noted that where rosin size is employed in alkaline filler paper mixes in the processes as disclosed in my prior Patents Nos. 1,803,643, and 1,803,647, a certain amount of rosin in unsaponified form may be present, which in the case of high free rosirs soaps may amount to the theoretically possible per cent. of the total rosin present as explained above.

In the present application I disclose a process comprising the use of sizes comprising saponifiable material in substantially completely unsaponified or preponderatingly unsaponifiecl form for sizing papers filled with alkaline filler. In its preferred practice the present process is a modification of the procedures covered broadly-by the two patents last referred to. Saponifiable materials of any type whether partially'or wholly saponifiable may be used in'the present process. Examples are: fatty acids, esters particularly glyceryl esters of saturated and unsaturated acids, and esters of the high molecular fatty acids with alcohols, saponifiable gums, resins and the like, all whether chemically pure or occurring commercially in combination or association with other materials. In the class of saponifiable materials, however, I do not intend to include such black or substantially black colored materials of a pitchynature which, because of their color, are not feasible for use in white papers, or even in papers which are somewhat colored such as kraft or the like.

1 preferably use saponifiable materials WlllCh are solid or substantially solid at ordinary or room temperature and from the standpoint of cost I prefer to use rosin. In

that of the rosin present in saponified form,

which differentiates from my prior disclosure.

The advantage of using saponifiable material in completely or preponderatingly unsaponified form rather than in saponified form is that in certain cases there is less tendency to foam formation. This is particularly useful in the case where coated broke is employed in the furnish. Also there is less tendency in certain cases for the web to stick to the press rolls or the like on the paper machine. Moreover in certain cases it is possible to effect an economy in the amount of sizing material employed as well as in the amount of alum used. There is also a tendency for the sizing to be less aflected by the deteriorating influence of alkaline filler.

Moreover the use as a size of saponifiable material such as rosin in completely or preponderatingly unsaponified form has an advantage over the use of parafiin, which is a substantially unsaponifiable material, because paraffin, although advantageous from the standpoint of increasing the flexibility of the sheet, has a tendency to weaken the sheet in respect tocertain of its strength tests, such as the bursting or Mullen test. This disadvantage rosin does not have, rosin in fact exerting substantially no deleterious effect on the strength of the sheet.

As has been fully described in my two prior patents las rred to, When an acidic agent such as a. utilized with a size in a relatively concentrated fibrous mix in the presence of an alkaline filler, there takes place a deterioration or destruction of the sizing by alkaline filler. This is avoided if materials are added to the mix according to the minimizing principle. The phenomena on which this principle is based have been described by me in great detail in these two patents last referred to as well as in numerous other of my issued patents.

Briefly the situation is that alkaline filler, which always is present in the stock from which paper filled with alkaline filler is made in great stoichiometrical excess over the acidic constituent, acts upon the acidic constituent to the ultimate destruction thereof and/or the destruction of the effect maintained by such constituent. (The acidic constituent socalled may be one which is actively acid, and/or one, such as a size precipitate. which is capable of being affected or deterioratm'l by an alkaline material.) The action just referred to has been found to depend upon the time of contact of the acidic and alkaline constituents and also upon the intimacy of contact of these constituents. Agitation such as normally occurs in pa 'iermaking procedure in stuff chests or the like accelleratw the rate of reaction, but agitation at low concentrations while having some effect is not nearly so deleterious. Based on these observed phenomena a. practical application has been developed whereby, by utilizing the minimizing principle, i. e. by minimizing the time and/or intimacy of contact of the acidic and alkaline constituents, the acidic constituent and/or the effect produced'thereby is substantially preserved in an alkaline filler mix. lVith the present types of paper machines and the present arrangement of equipment usually employed in paper machine operation, the contact of the acidlc material and the alkaline constituent at any time prior to the passage of the stock from the last stuff chest, which is commonly called the machine chest, re-

.sults in great deterioration or complete destruction of the acidic material. Addition of one or both of these constituents, as well as other materials such as size, sodium silicate, starch, or the like, as set forth in my various issued patents, at a point subsequent to the passage of the stock from the machine chest, after which point according to present day operating practice the stock remains in concentrated condition only for a very brief interval of time, or addition preferably at or subsequent to the point of dilution, i. e. at the wet end of the paper machine, serves to substantially conserve the acidic material and/or effect thereof in the fibrous mix. It is this so-called minimizing principle which I prefer to utilize in the practice of my invention.

In the preferred practice of my invention, there is prepared in any suitable container such as a beater, a fibrous mix of any desired fibrous constituents, to which is added alkaline filler, and size for example rosin in substantially or preponderatingly unsaponified form, preferably as an aqueous emulsion. A precipitant such asan acidic material, preferably alum, may then be added. A variation which is sometimes desirable to practice is to add the size and alum to the fibre prior to the addition of the alkaline filler. After any further desired treatment of the mix such as is customary to prepare it for use, it is then diluted preparatory to running off on the Webforming device. Preferably at this point a further amount of acidic material as alum may be added; or the original addition of alum may be omitted if desired and alum addedonlyatthedilutestage. Inthefirstinstance the alum added at the dilute stage acts as a restoring agent, in the second as the original precipitating or fixing agent. Various other orders of addition of materials may be used in accordance with the minimizing principle as has been set forth in my various patents or copending applications. For example, the alkaline tiller, alum, and/or size may be added at the dilute stage, as well as other constitnents of the mix. The mix is then run over a web-forming device and through the remainder of the customary equipment of a paper machine, such as driers, and calender-s, if desired, producing thereby a satisfactorily sized paper filled with alkaline filler. The paper produced by my process is thus what is known in the art as sized filled paper and by mere observation cannot be readily distinguished from ordinary clay filled paper sized with ordinary rosin size.

Emulsions for use in my process, such for example as those to be described below, may in certain cases be used directly with the alkaline filler in the fibrous mixture and run ofi on a web-forming device without the addition of alum according to the minimizing principle. In such case however, the emulsions are not fixed on the fibre, and thus much i the emulsion is lost in the white water, substantially the only amount remaining in the sheet being that which is mechanically retained by the web. When alum is employed as in the preferred practice of my invention outlined above,this sufiices to fix certain of the emulsions very satisfactorily on the fibre, and

others of them with a fair degree of satisfaction. However it is sometimes desirable to employ instead of alum, or additionally therewith, fixing agents such as two mutually precipitating or fiocculating materials. As alum itself 18 an excellent material for use as one of the mutually flocculati-ng agents, it is sometimes convenient to employ wit alum only one other material which with alum will form a flocculate or precipitate. Examples of mutually fiocculating materials which may be employed are: soluble salts such as sodium silicate and acidic material as hydrochloric acid; barium chloride and sodium sulphate; and the like. Examples of materials which fiocculate with alum are sodium hydroxide, sodium silicate, soap such as rosin soap; and the like. These may be added in the beater and/or dilute stage, but it is desirable that when the precipitation or flocculation takes place the emulsion l emplo should be already present in the mix.

ll is to be understood that my invention may be practiced without employing the min imizing principle. Thus the emulsion may be added with the fibre and alkaline fillerin the concentrated stage of the paper making operation as in the beater, without alum as described above, or in the beater with alum and with or without other fiocculating materials. While in certain cases moderately satisfactory results can thus be obtained, I prefer however to emplo the minimizing a principle as superior resu ts are usually obtained thereby.

In order that rosin in substantially or preponderatingly unsaponified form,-such as I employ in the practice of my invention, may be used in a fibrous mix, it is necessary that the rosin be introduced in extremely finely divided condition, preferably as afinely divided suspension or emulsion. Such suspensions or emulsions of rosin may be prepared in a number of ways.

For example, rosin may be thus emulsified by mechanical dispersion with a small percentage, for example about 2 per cent..of a protective colloid such as alkali casein according to the so-called Bewoid process to form the so-called Bewoid size, (see Canadian Patent No. 305,650 of November 11, 1930). When alkali casein is used for emulsifying rosin according to the Bewoid process an amount of alkali is usually employed with the casein which is somewhat more than that required to completely dissolve the casein. Thus a certain amount of unacted upon alkali comes in contact with the rosin which may result in the conversion of a small amount of the rosin into soap form. However this may be, it is within the bounds of reasonable commercial accuracy to state that therosin in Bewoid size is present substantially completely in unsaponified form.

Another suitable method is to emulsify rosin with a substantially insoluble type emulsifyin agent, for example such method as is descri ed for parafin in my issued Patents Nos. 1,803,651 and 1,803,652. This may be done by melting rosin and vigorously mixing the melted rosin with a paste formed of emulsifying material and a liquid such as h water, whereby the rosin becomes the disperse phase of the emulsion, the particles of rosin being substantially surrounded by the substantially insoluble emulsifying agent. Various emulsifying agents may be used, such for example as clay, more advantageously colloidal clay such as bentonite. A modification of this method is where the substantially insoluble emulsifying agent is formed by precipitation in the presence of finely dispersed particles of molten rosin in liquid suspension.

Still another suitable way in which rosin may be emulsified is by making a substantially non-breakable emulsion therewith such for example as is described for parafiin in my issued Patents, Nos. 1,803,645 and 1,803,- 648. In this case the melted rosin is emulsified with a solution ofa gum preferably substantially water soluble such as gum ghatti and other additive agents may be employed such as dextrin. One such emulsion may be made by the use (by weight) of 15 parts of In order to overcome the desirability of using such high temperatures as will make the is generally desirable to use only a minor amount, and such a minor amount is normall all that is necessary, 5 to 25 per cent. 13 usually sufticing. Suitable materials to use in conjunction with the rosin are parafiin,

rosin oil, petrolatum, or any other liquids, oils or fluxible solids which will lower the melting point or decrease the viscosity of the rosin 15 melt.

Other methods of preparing suitable emulsions are possible but these examples will suffice.

An example of a furnish suitable for carry- 29 ing out my invention is as follows:

Added in the beater Pounds Fibrous furnish, e. g. sulphite pulp, soda 25 pulp and old paper stock 1000 Alkaline filler, e. g. calcium carbonate magnesium hydroxide 200 Emulsion of saponifiable material in substantially unsaponified form, e. g.

33 rosin, (based on weight of rosin) Added continuously] and proportionately at dilute stage of the paperma/cing process Pounds 33 Acidic material, e. g. alum Another example is Added in the beater Pounds 4: Sulphite and soda pulps 700 Coated broke (containing about 70% fibre) 430 Alkaline filler, e. g. calcium carbonate magnesium hydroxide 100 Emulsion of saponitiable material in substantially unsaponified form, e. g.

rosin (based on weight of rosin) 17.5 Rosin size (based on weight of rosin)- 2.5 Acidic material, e. g. alum 1O Added continuously and proportionately at dilute stage Pounds Acidic material, e. g. alum 20 DJ Another example 15:

Added in the beater lounds Sulphite and soda pulps 700 Coated broke (containing about fibre) 430 Bewoid size (based on weight of rosin present) 2O Acidic material,e. g. hydrochloric acid 2 Alkaline filler, e. g. calcium carbonate Added continuousl and proportionately at dz ute stage Pounds Acidic material, e. g. alum 20 It is to be understood of course that these and proportions and order of addition, and

still obtain satisfactory results.

Instead of, or in addition to, introducing my emulsion into the fibrous mix, I may a ply it to the web, by which is intended to e included the web either durin the process of its formation or after it hasieen formed. This application to the web may take place either on the paper machine or subsequently. If desired, a precipitant or mutuall flocculating precipitants may be applie to the emulsion prior to its application to the web, or a precipitant or mutually flocculating precipitants may be applied to the web at the same time as the emulsion, or independently thereof. Any known method of making such application is suitable.

Where I use the word rosin, I intend to include not only the natural resin, but any synthetic resin acid or acids.

In place of alum I may use other aluminum salts or other metallic salts such as zinc sulphate or the like, or other acidic materials such as acid, sodium bisuiphate or the like.

By the term alkaline filler I mean substantially water insoluble filler which when agitated in contact with freshly boiled distilled water, say for an hour, will impart a pH value to such water greater than 7.0, that is, which will be on the alkaline side of the neutral point. Among fillers included in this group may be mentioned calcium carbonate, of which lime mud from the causticizing process is one form; calcium carbonate magnesium basic carbonate em loyed in the paper disclosed in my United tates Patent No. 1,595,416, issued August 10, 1926; calcium carbonate magnesium hydroxide disclosed in my United States Patent No. 1,415,391, issued May 9, 1922; and other substantially water insoluble normal or basic carbonates of alkaline earth metals (which expression is herein intended to include magnesium), or compounds, double salts, or physically associated mixtures of these with one or more other acid soluble materials of a substantially water insoluble nature.

By the term alkaline filler, I also intend to include fibrous material and/or other material such as paper coating constituents or the like containing one or more compounds of the character referred to, such as old papers or similar papers, broke or the like.

\Vhen I use the word paper herein, I use it in the broad sense to nclude products of and proportioning devices, rifiiers, troughs,-

screens, head boxes, inlets, and the like, including also instrumentalities used in the white water cycle.

lhe term fibrous mix or paper mix as used herein is intended to mean a mix of various constituents including fibre from which paper may be made, either alone or after the addition of other ingredients.

By the expression preponderating amount. I mean an amount more than fifty- .five per cent. of the total.

While I have described in detail the preferred embodiment ofmy invention, it is to be understood that the details of procedure, the proportions of ingredients, and the arrangement of steps may be widely varied without departing from the s irit of my invention or the scope of the su joined claims.

I claim: 1 1. In aprocess of manufacturing paper wherein a paper mix containing fibrous material and alkaline filler is prepared and then run off on a web-forming device and wherein there is added size comprising saponifiable material, said size being added at at least one of a group of points consisting ofthe paper mix and the web, the improvement which comprises adding the substantially 'preponderating amount of said saponifiable material in unsaponified form.

2. In a method of manufacturing sized paper filled with alkaline filler, the step of adding to the paper m x from which said paper is to be made saponifiable material substantially completely in unsaponified form.

3. In a method of manufacturing sized paper filled with alkaline filler, the step of adding to the paper mix from whichsaid paper is to be made an emulsion of saponifia ble material substant ally completely in un-' saponified form.

4. In a method of manufacturing sized paper filled with alkaline filler, the step of adding to the paper mix from which said paper is to be made an emulsion of saponifiable material of which the substantially preponderating amount is present in unsaponified. form.

5. In a method of manufacturing sized paper filled with alkaline filler, the steps of adding to the paper mix from which said paper is to be made saponifiable material substantially completely in unsaponified form and acidic material.

6. In a method of manufacturing sized paper filled with alkaline filler, the steps of adding to the paper mix from which said paper is to be made saponifiable material substantially completely in unsaponified form and alum.

7. In a method of manufacturing size paper filled with alkaline filler, the steps of adding to the paper mix from which said paper is to be made an emulsion of saponifiable material substantially completely in unsaponified form and precipitant therefor.

8. In a method of manufacturing sized paper filled with alkaline filler comprising calcium carbonate, the steps of adding to the paper mix from which said paper is to be made an emulsion of saponifiable material substantially completely in unsaponified form and precipitant therefor.

9. In a method of manufacturing sized paper filled with alkaline filler comprising calcium carbonate and magnesium comound, the steps of adding to the paper mix emulsion of saponifiable material substantially completely in unsaponified form and precipitant therefor.

10. In a method of manufacturing sized paper filled with alkaline filler comprising calcium carbonate magnesium hydroxide, thesteps of adding to the paper mix from which said paper is to be made an emulsion of saponifiable material substantially completely in unsaponified form and precipitant therefor. I i

11. In a method of manufacturing sized paper filled with alkaline filler, the steps of adding to the paper mix from which said paper is to be made an emulsion of saponifiable material substantially completely in unsaponified form and acidic material.

rom which said paper 1s to be made an v 12. In a method of manufacturing sized paper filled with alkaline filler, the steps of adding to the paper mix from which said paper is to be made an emulsion of saponifiable material of which the substantia ly preponderating amount is present in unsaponified form and acidic material.

'13. In a method of manufacturing paper filled with alkaline filler wherein material is added to a paper mix under conditions favoring the minimizin of the time and/or intimacy of contact 0 the constituents of the mix, the step of addingspo said paper mix saponifiable material su antially completely in unsaponified form.

14. In a method of manufacturing paper filled with alkaline filler wherein material is added to a paper mix under conditions favoring the minimizing of the time and/or intimacy of contact of the constituents of the mix, the step of adding to said paper mix an emulsion of saponifiable material substantially completely in unsaponified form.

15. In a method of manufacturing paper filled with alkaline filler wherein material is added to a paper mix under conditions favoring the minimizing of the time and/or intimacy of contact of the constituents of the mix, the step of adding to said paper mix an emulsion of saponifiable material of which the substantially preponlerating amount is present in unsaponified form.

16. In a method of manufacturing paper filled with alkaline filler wherein material is added to a paper mix under conditions favoring the minimizing of the time and/or intimacy of contact of the constituents of the mix, the steps of adding to said paper mix saponifiable material substantially completely in unsaponified form and acidic material. H

17. In a method of manufacturing paper filled with alkaline filler wherein material is added to a paper mix under conditions favoring the minimizing of the time and/or intimacy of contact of the constituents of the mix, the steps of adding to said paper mix saponifiable material substantially com-,

is added to a paper mix under conditions favoring the minimizing of the time and/or intimacy of contact of the constituents of the mix, the steps of adding to said paper mix an emulsion of saponifiable material substantially completely in unsaponified. form and acidic material.

20. In a method of manufacturing paper filled with alkaline filler wherein material is added to a paper mix under conditions favoring the minimizing of the time and/or intimacy of contact of the constituents of 7 the mix, the steps of adding to said paper adding Bewoid size to the paper mix from which said paper is to be made. 7

23. In a method of manufacturing sized paper filled with alkaline filler, the step of adding to the paper mix from which said paper is to be made an emulsion of rosin substantially completely in unsaponified form.

24. In a method of manufacturing sized paper filled with alkaline filler, the step of adding to the paper mix from which said pa per is to be made an emulsion of rosin of which the substantially preponderating amount is present in unsaponified form.

25. Ina method of manufacturing sized paper filled with alkalinefiller, the steps of adding to the paper mix from which said paper is to be made rosin substantially completely in unsaponified form and acidic material. c

26. In a method of manufacturing sized paper filled with alkaline filler, the steps of adding Bewoid size and acidic material to the paper mix from which said paper is to be made. i

27. In a method of manufacturing sized paper filled with alkaline filler, the steps of adding to the paper mix from which said paper is to be made rosin substantially completely in unsaponified form and aliim.

28. In a method of manufacturing sized paper filled with alkaline filler, the steps of adding Bewoid size and alum to the paper mix from which said paper is to be made.

29. In a method of manufacturing sized paper filled with alkaline filler, the steps of adding to the paper mix from which said paper is to be made an emulsion of rosin substantially completely in unsaponified form and precipitant therefor;

30. In a method of manufacturing sized paper filled with alkaline filler, the steps of adding to the paper mix from which said paper is to be made an emulsion of rosin sub- 7 stantially completely in unsaponified form and acidic material.-

31. In a methodof manufacturing sized paper filled with alkaline filler, the steps of adding to the paper mix from which said paper is to be made an emulsion of rosin of which the amount is present in unsaponified form and acidic material.

32. In a method of manufacturing paper filled with alkaline filler wherein material is substantially preponderating added to a paper mix under conditions favoring the minimizing of the time and/or intimacy of contact of the constituents of the mix, the step of adding to said paper mix rosin substantially completely in unsaponified form. V

83. In a method of manufacturing paper filled with alkaline filler wherein material is added to a paper mix under conditions favoring the minimizing of the time and/or intimacy of contact of the constituents of the 7 mix, the step of adding Bewoid size to said paper mix.

34. In a method of manufacturing paper filled with alkaline filler wherein material is added to a paper mix under conditions favoring the minimizing of the time and/or intimacy of contact of the constituents of the mix," the step of adding to said paper mix an emulsion of rosin substantially completely in unsaponified form.

35. In a method of manufacturing paper filled with alkaline filler wherein material is added to a paper mix under conditions favoring the minimizing of the time and/or intimacy of contact of the constituents ofthe mix, the step of adding to said paper mix an emulsion of rosin of which the substantially preponderating amount is present in unsaponified form.

36, In a method of manufacturing paper filled with alkaline filler wherein material is added to a paper mix under conditions favoring the minimizing of the time and/or intimacy of contact of the constituents of the mix, the steps of adding to said paper mix rosin substantially completely in unsaponi fied form and acidic material.

37. In a method of manufacturing paper filled with alkaline filler wherein material is added to a paper mix under conditions favoring the minimizing of the time and/or intimacy of contact of the constituents of the mix. the steps of adding Bewoid size and acidic material to said paper mix.

38. In a method of manufacturing paper filled with alkaline filler wherein material is added to a paper mix under conditions favoring the minimizing of the time and/or intimacy of contact of the constituents of the mix, the steps of adding to said paper mix rosin substantially completely in unsaponified form and alum.

39. In a method of manufacturing paper filled with alkaline filler wherein material is added to a paper mix under conditions favoring the minimizing of the time and/or intimacy of contactof the constituents of the mix, the steps of adding'Bewoid size and alum to said paper mix.

all). In a method of manufacturing paper filled with alkaline filler wherein material is added to a paper mix under conditions favoring the minimizing of the time and/or intimacy of contact of the constituents of the mix, the steps of adding to said paper mix an emulsion of rosin substantially completely in unsaponified form and acidic material.

42. In a method of manufacturing paper filled with alkaline filler wherein material is added to a. paper mix under conditions favoring the minimizing of the time and/or intimacy of contact of the constituents of the mix, the steps of adding to said paper mix an emulsion of rosin of which the substantially preponderating amount is present in unsaponified form and acidic material.

43. In a method of manufacturing sized paper filled with alkaline filler, the step comprising applying to a fibrous web containing alkaline filler 'saponifiable sizing material of which substantially the preponderating amount is in unsaponified form.

44. In a method of manufacturing sized paper filled with alkaline filler, the step comprising applying to a fibrous web containing alkaline filler an emulsion of saponifiable sizing material of which substantially the preponderating amount is in unsaponified form.

iii. In a method of manufacturing sized paper filled with alkaline filler, the step comprising applying to a fibrous web containing alkaline filler an emulsion of rosin in a substantially water soluble gum.

46. in a method of manufacturing sized paper filled with alkaline filler, the step comprising applying Bewoid size to a fibrous web containing alkaline filler.

47. Sized filled paper comprising fibrous material, alkaline filler, and saponifiable sizing material substantially completely in unsaponified form. r

48; Sized filled paper comprisin fibrous materiahvalkaline filler, and saponi able sizing material substantially completely in un saponified form and colloidal material.

49. Sized filled paper comprising fibrous material, alkaline filler, and rosin substantially completely in unsapbnified form.

50. A sized paper comprising fibrous material, alkaline filler and rosin derived from an emulsion thereof in a substantially water soluble gum.

51.-'A sized paper comprising fibrous material, alkaline filler and rosin derived from Bewoid size.

52. Sized filled paper comprising fibrous surface derived from raw materials including colloidal material and saponifiable material.

55. Sized filled paper comprising fibrous material, alkaline filler,- and sizing on the surface comprising rosin substantially completely in unsaponified form.

In testimony whereof I afiix my signature.

HAROLD ROBERT RAFTON. 

